A paucity of knowledge exists about neonatal trace element nutrition requirements, especially for premature infants, whose critical final trimester accumulation of essential trace elements is abruptly ceased at birth. The objective of this proposal is to develop the science and technology "bridge" required to demonstrate the feasibility of direct, or nearly direct, determination by resonance ionization mass spectrometry (RIMS) of sub-nanogram quantities of Mo, Cu, and V in less than or equal to 0.1 cm-3 blood samples from premature infants. Specifically, the aims are: (1) To investigate and apply resonance ionization schemes for the elementally selective ionization of Mo, Cu, and V; (2) To develop isotope dilution analysis methodology for samples with minimal chemical preparation; (3) Demonstrate the feasibility of measurement of sub-nanogram quantities of Mo, Cu, and V; (4) Demonstrate how the integration and application of the above components can lead to the significant advancement of neonatal nutrition and how the concept of this new ultratrace analytical tool can be expanded and applied broadly to elements and isotope analysis. The longer term (Phase II) objectives would be: (1) To design and construct a cost effective commercial prototype RIMS system that incorporates simplicity of construction and use and a maximum of elemental and isotopic measurement flexibility; (2) To demonstrate the application of knowledge and insight from Phase I to the solution of specific problems in neonatal nutrition.